Table 1.
Resistance phenotype, genotype, and genetic elements of E. coli strain W635, transconjugants (TC), and recipient straina
| Strain | MIC (μg/ml) ofb: |
Resistance gene(s) | Amino acid change(s) detected |
Class 1 integron | Incompatibility group detected (size of plasmid) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AMP | ATM | IPM | MEM | STR | TMP | GyrA | ParC | |||||||
| W635 donor | >128 | 8 | 128 | 32 | 128 | >128 | blaTEM-1b | blaIMI-2 | strA-strBc | sul1 sul2 | S83L, D87N | S80I | dfrA1 aadA1 | IncI1 (97 kb), IncF (48.5 kb), ColETP (<10 kb) |
| TC1 | >128 | 8 | 128 | 16 | >128 | >128 | blaTEM-1b | blaIMI-2 | strA-strB | sul1 sul2 | ND | ND | dfrA1 aadA1 | IncI1/IncF (160 kb),d ColETP (<10 kb) |
| TC15 | >128 | 0.125 | 0.25 | 0.032 | >128 | >128 | blaTEM-1b | – | strA-strB | sul1 sul2 | ND | ND | dfrA1 aadA1 | IncI1 (97 kb) |
| CSH26 recipient | 16 | 0.125 | 0.25 | 0.032 | 4 | <0.125 | – | – | – | – | ND | ND | ND | ND |
a
ND, not determined; –, not detected.
b
AMP, ampicillin; ATM, aztreonam; IPM, imipenem; MEM, meropenem; STR, streptomycin; TMP, trimethoprim.
c
strA-strB genes were linked to the sul2 gene (repC-sul2-strA-strB-ISCR2).
d
IncI1 and IncF were detected by hybridization in a plasmid of approximately 160 kb in the blaIMI-2-positive TC1 transconjugant.